a cell of the peripheral nervous system that wraps around a nerve fiber, jelly roll fashion, forming a myelin sheaths

1 cell = 1 myelin segment

guides azonal regeneration

tough fibrous membrane forming the outermost of the three coverings (meninges) of the brain and spinal cord

-outermost under the skull

-protects the CNS

dura mater = tough mother

the delicate, thin, fibrous, and highly vascular membrane forming the intermost of the three coverings of the brain and spinal cord

pia mater = gentle mother

thin membrain of the CNS that is between the dura mater and the pia mater

cob web like

the largest neuroGLIA cells of nervous tissue

also called astoglia

-they cover the blood vessels

-contact neuronal cell bodies

-exchange chemicals with adjacent neurons

-smaller than astrocytes

- (scavengers) remove waste materials

hindbrain -> metencephalon -> cerebellum

-"little brain"

-play role in motor functions (coordinated movements) like balance and riding a bike, bodily equillibrium, posture,

-now evidence exists for a role in cognition

forebrain -> diencephalon -> hypothalamus

DRIVER

-controls ANS and endocrine system by regulating sleep cycles, body temp, bp, thirst, appetite, mesolimbic system and producing hormones from pituitary gland via infundibular stalk-hormonal and neural messages

pituitary gland is the mouth pieces of hypothalamus

Four F's - feed, fight, flight, fuck

forebrain -> diencephalon -> basal ganglia

-to the left and right of thalamus, comprised of 3 major structures

-caudate nucleus, putamen, globus pallidus

-exchanges of info with cortex

-planning motor sequences of behavior

-certain aspects of memory and emotional response

-disruptions hers -> huntington's disease and impairs motor abilities

hindbrain -> myencephalon -> medulla

-stalklike, continuous with the sppinal cord

-control centers for heart and lungs, CVS cardiovascular system, respiration

-gives us the ability to sit up (skeletal muscle tonus)

-most caudal portion of the brain stem -- nuclei here control vital functions

A-

Anions, inside the cell, part of its machinery, and they won't go through the cell membrane

-result in a net negative charge inside the cell

-phosphate group portion is polar (the head) and is hydrophilic

-hydrocarbon is nonpolar (the tail) and is hydrophobic

-stable arrangement of two layers

-forms a barrier to water soluble ions - charged molecules

-group of fatty compounds

-small gaps in myelin sheath

-part of CNS

hindbrain -> metencephalon ->

1. cerebellum - already defined

 2. pons (bridge)

-sensory and motor tracts cross from one side of the brain to the other

-contains nuclei for cranial nerves

-reticulum (net) or reticular system -> arousal

midbrain -> mesencephalon ->

1. tectum- "roof" with 4 "bumps"

-2 superior colliculus -> visual reflexes and saccades (horizontal movements)

-2 inferior colliculus -> loud sudden noises

2. tegmentum - "covering" like a rug on a floor

-parts of the reticular formation - attention and sleep cycles

-pathways between forebrain and spinal cord

3. "headwaters" of 2 major dopamine tracts

a. nigrostriatal system - important for initiation of movement, project to caudate nucleus and putamen

b. mesolimbic system - DA releasing neurons project to limbic structures - emotions, and motivated behaviors, activation in eating, sex, escape from noxious stimuli, overactivity can cause schizophrena

forebrain -> diencephalon ->

1. thalamus- "hand-maiden" (messenger) of the cortex

-relay of ascending sensory and descending motor info

-switchboard

-lumps (a.LGN info from eyes to primary visual cortex

b. MGN info from inner ear to primary auditory complex

2. hypothalamus - covered

3. basal ganglia - covered

4. limbic system - a. motivated and emotional behavior

b. sets of structures forming a ring around the brain stem

-amygdala "almond" ->fear/anxiety, aggression

-hippocampus "sea horse" -> linked to hypothalamus-memory

-cingulated gyrus of cerebral cortex

-hypothalamus

-septum- pleasant, sexual feelings

-mammillary bodies

*helps you "feel" what is good or bad so it can preform right behavior in complex environment (adaptive)

-cations (positive charge)-

sodium

-more Na+ outside the cell (membrance only permits a little to leak through at a time)

ex. underage drinkers- some get in with fake id the the bouncers throw 3 out at a time and bring in 2K+

-cations (positive)

-Potassium

-more K+ inside (membrane only permits a little to leak out)

-Concentration gradient - Brownian movement - forces molecules out to where there is more room - more K+ will leak out

electrical gradient- neg charge inside will bring K+ back in

ex. legal drinkers, when 3 Na+ are thrown out, 2 K+ are brought in

-anion (negative)

-found mostly outside the cell

ex. passerbys of the bar

-cation (positive)

-phospholipid bilayer

a. 2 layers of fat molecules

b. protein molecules are embedded in these sheets (channel and signal proteins)

-hydrophbic tails of molecules are nonpolar

-hydrophilic heads of molecules are polar

axon hillock - here that Na+ channels open when there is enough pos charge

-depolarization- make less different - pos charges come in, then K+ channels open to let K+ out

-repolarization - make different again

K+ channels gradually close, but too many flow out

-hyperpolarization - even more different

-refractory period- for about 1-2 ms after AP there cannot be another one

-relative refractory period- need more stimulus because of hyperpolarization

Wakefield's hybrid account of mental disorder

-2 componets

-how do they differ

HARMFUL DYSFUNCTION - harm is a value and dysfunction is factual

1. both values and facts are involved in concept of disorder

2. a dysfunction exists only when and organ cannot perform a relevant natural function

3. disorder lies in the boundary between the natural world and the constructed social world so simultaneously BIOLOGICAL AND SOCIAL

Describe the division of the nervous system

-system of 2's

1. Central Nervous System

a. skull (brain) and spine (spinal cord)

2. Peripheral Nervous System

1)Somatic Nervous System (body)

a. interacts with external environment

b. afferent nerves carry info to CNS (hit your hand on hot stove and get a shock of pain)

c. efferent nerves carry info from motor neurons to skeletal muscles (pull hand away from pain)

2)Autonomic Nervous System (automatically)

a. regulates  internal environment

b.affterent nerves carry info from internal organs to CNS

c. efferent nerves carry info from CNS to internal organs

d. 2 divisions

i.)Sympathetic Nervous System - running from a bear

ii.)Parasympathetic Nervous System - safe from bear so now you can go back to normal (start digesting again, relax)

31 pairs of spinal nerves

12 pairs of cranial nerves

cerebral spinal fluid

where is it found?

how is it produced?

where is it absorbed?

what condition is it when the flow is blocked?

found in the subarachnoid space, central canal of spinal cord, and ventricles of brain

produced by choroid plexuses

absorbed into large blood-filled spaces called dural sinuses

if its blocked - hydro(water)encephalus(brain)

blood brain barrier

what can cross?

what cannot?

-helps maintain precise electrochemical balance and keep out toxins

-cells of blood vessel walls are packed (tight junctions)

-proteins and other large molecules cannot cross

-fat soluble molecules can cross like sex hormones, some drugs, glucose

what is myelin?

what cells produce it in CNS?
what cells produce it in PNS?

-myeline insulates and increases speed of transmission of neural messages

-oligodendrocytes form myelin sheaths around axons of some neurons in CNS

-schwann cells form myelin sheaths in PNS

embryological development of the CNS in vertebrates

from what does the CNS develop?

what are the buldges that develop?

what do the buldges become?

developed from ectoderm - neural plate, neural groove, neural fold, neural tube

CNS develops from fluid filled neural tube

-neural ectoderm tissue is pinched off as the neural folds come together, called the neural crest, and becomes PNS neurons

mesoderm forms buldges called somites which become 33 individual vertebrae

buldges are forebrain, midbrain, and hindbrain

Forbrain - telencephalon, diencephalon

Midbrain - mesencephalon

Hindbrain- medulla, metencephalon

phospholipid membrane

1.phosphate group portion is polar (the head) and is hydrophilic

2. hydrocarbon is nonpolar (the tail) and is hydrophobic

3. stable arrangement of two layers

4. forms a barrier to water souluble ions - charged molecules

part of the CNS, brain and spinal cord are covered by meninges - protective membranes

a. dura mater - (tough mother) outermost, under skull

b. arachnoid - (web like) under dura mater

c. pia mater - (gentle mother) innermost, very thin

describe the thalamus

which part of brain?

primary roles?

 forebrain -> diencephalon -> thalamus

-"hand maiden" of cortex - messenger

-relay of ascending (sitting uncomfortably) sensory and descending (change position) motor info

-switchboard

-lumps

1. lateral geniculate nuclei (LGN) into from eyes to primary visual cortex

2. medial geniculate nuclei - info from inner ear to primary auditory complex

what is the limbic system?

know three structures of this system

a. motivated and emotional behaviorss

b. sets of structures forming a ring around the brain stem

1. amygdala (almond) -> fear/anxiety, aggression, mating

2. hippocampus (sea horse) -> linked to hypothalamus, plays an important role in memory (convert short term to long term)

3. cingulated gyrus of cerebral cortex

4. hypothalamus

5. septum pleasant -> sexual feelings

6. mammillary bodies -> important for the formation of memories

-helps organism "feel" what is good or bad so it can perform right behavior in complex environment (adaptive)

what is potential?

what are the four factors involved in maintaining the resting membrane potential?

why is it worth spending energy to maintain this potential?

-potential is the difference in electrical charge between inside and outside of cell

1. selective permeability (lipids, glucose, and some hormones can pass)

IONS

-more Na+ outside (membrance only lets a little leak in)

-more K+ inside (membrane only lets a little out)

-Cl- is found mostly outside

-Large protein molecules A- are inside - part of cell, wont go through membrane

-> result in net negative charge in cell

2. Sodium Potassium Pump

a. need 1/2 of total cell energy

b. grabs 3 Na+ that leaked in and throws them out and 2 K+ that leaked out and bring them in

-generates a potential, since you are sending out three pos and only bringing in two

3. Concentration Gradient

a. Brownian movement - any molecule that is warmer that absolute 0 is vibrating which forces to where there is more room

b. if you have 1000 K+ inside and only 100 outside they will move out

c. b/c of concentration gradient that the sodium potassium pump exists

ve the tendency to leak out, promotes net neg charge

4. Electrical Gradient

a. neg charge inside will attracts some K+ back in

b. there is really a compromise between the concentration and electrical gradient

* -70 mv really reflects the ability of K+ ions to seek out equilibrium

worth spending energy because you need to get back to resting potential for another action potential to take place

what is the absolute refractory period?

how long does it last for?

what are the implications for this for the neurons rate of firing?

limits 1000x per second

based on the two forms of conductions of action potentials

1. electrotonic ion flow -under myelin, Na+ elbow eachother losing energy, faster than

2. regenerative ion flow - AP get retriggered at each node of Ranvier, more Na+ flows in through channels, slower than electrotonic, but more sure to make it to the end

saltare means "to dance" - the two forms together

1. you get the best of both worlds

2. advantages

A. economy - because Na+ can enter a myelinated axon only at the node of ranvier, there are no useless regenerations

a. sodium-potassium transporter do not need to be so numerous or work so hard

b. this conserves energy

c. non-mylinated would be slow!

B. speed - transmission between the nodes is very fast

what is exocytosis?

how does it occur?

the process of neurotransmitter release

how -

a. AP's stimulate voltage-activated calcium (Ca ++) channels

b. they open and Ca++ ions can enter from the outside

c. Ca++ entry causes synaptic vesicles to fuse with presynaptic membrane and empty their contents into the synaptic cleft

-can inhibit or excite the postsynaptic neuron

What are the 4 lobes of the cortex?

What is a major role of each?

1. occipital lobe - receives input from visual pathways (PVC)

damage=cortical blindness

-see stars

2. parietal lobe - processing of body sensations, info, integration of modalities, pressure, touch, and pain

3. temporal lobe - target for auditory info

left -> understanding of spoken language

more complex aspects of vision

-agnosia -> failure to recognize not attributed to a sensory deficit or verbal or intellectual impairment

-recognition of faces -> prosopagnosia

-preception of objects -> visual agnosia

-role in emotional and motivational behaviors (kluver-bucy syndrome)

-rhinal fissure -> separates more ancient cortex from neocortex

4. frontal lobe - reasoning, motor skills

-receives input from all sensory modalities

-higher cognitive processes (working memory, social inhibition, emotional expression) *Phineas Gage

agonist

Where does the serotonergic system originate?  Project?

Know the classes of neurotransmitters listed in your handouts.  Know the class

each of the following neurotransmitters belong to:  glutamate, GABA, DA, Epi, NE, Serotonin, nitric oxide, carbon monoxide, acetylcholine.

1. Amino Acid neurotransmitters (smaller)

a. Glutamate (excitatory, very fast)

b. Glycine

c. GABA (inhibitory - opposite of glutamte, slow)

d. Aspartate (like aspertame)

2. Monoamine neurotransmitters

a. Catecholamines

-Dopamines (schizophrenia, parkinsins, depression, rewards)

-Norepinephrines (anxiety)

-Epinephrine (adrenaline)

b. Indolamines

-Seroonin

3. Acetylcholine (slows heart rate)

4. Soluble-Gas Neurotransmitters

a. Nitric Oxide (short half life, high=damage neurons, kill brain cells, lowers blood pressure)

b. Carbon Monoxide (very short half life)

two methods of influence for the avtivation of receptors by neurotransmitter molecules

a. ionotropic - ion channel linked receptors

1. channel usually opens or closes immediately leading to PSP (post synaptic potential) (charge)

2. a neurotransmitter may open an Na+ channels and depolarize or K+ channels and hyperpolarize

3. tend to be a fast, but short-lived effect

4. ligand-activated ion channels

b. metabotropic- signal proteins and G-protein linked receptors

1. attached to a portion of the signal protein outside the neuron, the G protein is attached to a portion of the signal protein inside the neuron

2. a subunit of the G protein breaks away and does one of two things:

-may move along and bing to nearby ion channel

-trigger synthesis of a second messanger which diffuses through the cytoplasm and either: binds to ion channel (she asks me to go make copies) or influences metabolism of cell (i ask sharon to make copies) or enters nucleus and influences gene expression (get into copier and make copies)

3. usually slower, more diffuse and varied effects but relatively long-term

4. more prevalent that ionotropic receptors

What is an autoreceptor?  (receptors on presynaptic membrane which binds it’s

own NT and can monitor and decrease release of that NT.)

Know what post synaptic potentials are.  They include EPSPs and IPSPs.  They

are graded reponses - that is, their amplitude are proportional to the intensity of the signals that elicit them. 

EPSP (excitatory postsynaptic potential) - postsynaptic depolarization

-decreases the resting membrane potential

-increases the chance that the neuron will fire

IPSP (inhibitory postsynaptic potential) - postsynaptic hyperpolarization

-increases the resting membrane potential

-decreases the chance that the neuron will fire

-both are graded responses - their amplitudes are proportional to the intensity of the signals that elicit them

-thus, synapses near the axon hillock trigger zone have the most influence

What synapses have the most influence on whether a neuron will fire or not?

(remember the axon hillock)

1. reuptake

a. more common

b. drawn back up into the terminal by transporters, repackaged in vesicles by golgi complex and re-released

2. enzymatic degradation

a. neurotransmitters are broken apart in the synapse by enzymes (chemicals that stimulate or inhibit chemical reactions without directly participating in them)

b. the main mechanism of inactivation for some NTs (e.g. acetylcholine)

functional deficiency or depletion of norepinephren or serotonin.

problems:

a. most antidepressant drugs that work at monoamine synapses have immediate effects there, but symptoms are not relieved for 2-8 weeks. the inconsistancy of time course of treatment with effects on mood suggests that some slow-developing consequence of the drug treatmetn is important.

b. some drugs that block monoamine reuptake do not have antidepressant effects (e.g. cocaine)

c. some therapies do not block monoamine reuptake, yet are antidepressants (e.g. lithium)

d. measurements of monoamines and their metabolites in depressed peopl are not always abnormal

What is the monoamine receptor hypothesis of depression? 

1. terminal autoreceptors - 5HT1D - when stimulated, blockade of 5HT release

2. somatodendritic autoreceptors - 5HT1A - when stimulated, shuts down neuronal firing

3. postsynaptic regulatory receptor - 5HT2A - when stimulated, causes neuron to fire

Know that the 5HT2A receptor is a key postsynaptic receptor that when stimulated increases neuronal firing. 5HT1D receptors are autoreceptors located on the presynaptic terminal that blockthe release of 5HT when stimulated.5HT1A receptors are autoreceptors which are located on the soma and dendrites of the presynaptic neuron.When they are stimulated, they shut down neuronal firing.These receptors are downregulated after more 5HT is in the system.

in order to manifest an overt psychiatric disorder, one must sustain the first hit of a genetic vulnerability, and a second hit of some type from the environment

environment can include genome, viruses, toxins, diseases, life stressors, personality, coping skills, social support

desynchroniztion is when physiological rhythms that are supposed to change together break apart. For example, sleep. temperature, and cortisol release are all supposed to be associated )low cort, low temp, and onset of sleep) With desynchroniztion you may have high cortisol levels or temperaature at a time when your sleep centers are trying to get you into your sleep stages.

1. consistent with the multiple chemical and physiological abnormalities found in depression

2. could explain the slow latency of clinical response to meds

3. relapse would be expected if continuing environmental factors or stimuli disrupt rhythms (shift workers)

What is the result of stress and excess glucocorticoid release on brain cells?  What

does the article about a new theory of cell growth and depression suggest is the relationship between these two states?  (What does the new theory suggest is the cause of depression?)

glucocorticoids (from stress) can disrupt neuronal connections and cause cell atrophy and death, also inhibit growth

hippocampus is smaller in patients with depression, and several ADs seem to increase brain cell growth, so disruptions in this cycle of cell growth may lead to depression

5HT neurons are usually silent during REM sleep

if you deprive REM sleep then it reduces depressive symptoms by increasing 5HT

major populations of 5HT neurons are silent during REM, therefore, reducing REM sleep will reult in more 5HT being released during a 24 hour cycle

ECT

exercise

REM deprivation

stimulating new brain cell growth

a lot like schizophrenia in the manic phase

when neuropsychologiccal deficits are present, most studies indicate greater visuospatial or right hemisphere dysfunction

when symptoms are under control, they can function at high level

presence of cognitive distortions

a. decreased fatigue levels and increases self esteem

b. not always euphoria

increased melatonin from pineal gland

increased plasma luteinizing hormone levels

subclinical thyroid dysfunction

abnormalities in cortical function/activity

a. variation in glucose metabolism

-regions of left frontal (prefrontal), temporal, and parietal lobes show decreased metabolic activitiy in depressed patients, excessive activity in mania

Know the main therapies used for treating Bipolar Disorder as listed in your outline.

a. neuroleptics -> antipsychotics

1. reduce dopaminergic transmission

2. used to treat schizophrenia

b. tricyclics (increase serotonin, dopamine, norepinephren) lead to mania

1. they increase catecholamine levels including DA

2. high levels of DA in certain brain regions produce effects similar to manic hyperactivity and thought processes

a. lithium - both antidepressant and antimanic, has notable effects on circadian rhythms

b. ECT - usually superior to lithium in antimanic effect , resets biological rhythms

c. Cognitive therapy

anphetamines produce effects similar to mania

they block reuptake of DA and reverse the transporters

What is melatonin?  Where is it produced?  What are melatonin levels like in Bipolar patients?

regular sleep cycles

produced in pineal gland

bipolar patients have increased levels of melatonin

What is the difference between MAOI, Tricyclic, and SSRI antidepressants?

MAOI - monoamine oxidase inhibiors

1. iproniazid is used first to treat TB

2. blocks monoamine oxidase in the cytoplasm of neuron

3. "cheese effect" if there is not enough monoamine oxidase, the amine tyramine, found in cheese and some other foods, elevates blood pressure to dangerous levels

Tricyclic -

1. imipramine is the first used antischizophrenic drug

2. blocks reuptake of NE and 5HT, increases stimulation of postsynaptic cell

3. safer than MAOIs

SSRI - serotonin selective reuptake inhibitor

1. prozac (fluoxetine)

2. different structure than tricyclics

3. selectively block 5HT reuptake

4. effective for many, but some side effects include headache, anorexia, sexual dysfunction